Expanding the Outdoor System

I should be getting my new AZFlo 2400 pump this week.  This will be my pick up tube.

Slots cut in 2" PVC DWV and wrapped with cooler pad.

Hopefully this will keep the mosquito fish from getting sucked up

This is my new grow bed built from a bunk feeder and using the GW Raft system.  Maybe I should have followed Giorgio's design more closely, but I think this will work.  I wanted to be able to lift the rafts independent of the pontoons, so I switched it up a little.
Rather than a straight tube, my pontoon is shaped like an 8 and is made of PVC DWV pipe because PVC cellular core is lighter than regular PVC pipe, but not as expensive as ABS which is also cellular and lighter than Sch 40 PVC.  Actually PVC DWV is about 40 cents a foot less expensive than Sch 40 or ABS.  You may have to go to a real plumbing store rather than and Big Box store to find it.  I've got hundreds of dollars in just the pipe.  This is a way to save a lot of money.
The holes are cut into FRP board which will be smooth and easy to clean.

 GW Raft System 

Giorgio did a great job of documenting the construction so here is a copy of  his post with a link to the original thread.

Link to Post
On January 17 & 18, 2012 Giorgio posted an idea for the GW Raft

Comment by Giorgio on January 17, 2012 at 5:10pm

I’ve been doing backyard aquaponics for almost 4 years now and I was doing mainly the Raft system using the styrofoam boards from HD, (I have no choice, I live in a small Island).

These board get waterlogged  rather quickly and working with them is very messy and you have to do so much work with them.  Finally I got tired of buying new foam and making new rafts and I figured out a way to make them last longer,  I got some FOOD GRADE epoxy and painted the bottoms that touch water and they seem to be doing good so far but still you need to put some sort of aeration in the grow bed for plants to grow better which will required space, time and money (resources).

Finally I came up with a great solution which will create aeration naturally and is pretty cheap and easy to build.   I teach a Aquaponics class in the backyard and many of my student were impressed with the new design and after a few crops I feel confident that is a great way to go and I want to share with the AP community.

FYI:  I’ve dome my research and I’ve talked to the manufactures of some of these products that I use but you are welcome to double check and share.

I took some pics and I will try to explain how I did it.

The top is called Polywall from HD and I cut it to 2x4 pieces for easy handling u can make them bigger if you wish.

The pontoons are 2" PVC pipe with caps I don't use glue just silicone

I used 1/2 pipe for the frame, you can get all T's and Elbows anywhere (HD) cheapest.

I used stainless 1/4" screws to sucure the Polly the the frame

and I used zip ties to secure the frame to pontoons.

You don't want to make any holes in the pontoons or it won't float.

These are so easy to make and no need for painting and no mess and the 2" net pot just barely touch the water (which is what we want)

The only thing will be  to figure out some sort of clip to secure the raft to the side of the grow bed when plants get big and heavy  cause it will sink a bit

Have fun

Giorgio

Comment by Giorgio on January 18, 2012 at 2:02pm

Aloha !

Here are a couple more pics to give you better idea.

The GM Raft System

This design is fricking awesome...I'm growing lettuce almost  2x faster than regular foam rafts and cause the only part of the raft that touches water is the 2" pontoon there is lots of aeration underneath the root system (WITHOUT) the need of air stones, valves, siphoning or any other device.

Is very simple concept that works great, I'm sure whoever tries it will love it and is less than 1/2 the cost of the foam rafts and  about 75% less work without the mess and once you get one going you can make a bunch at a time.

I used 3 screw at the ends and 4 on the sides, make sure to use stainless

Have fun...